Concentrate take-off devices for pinched launder concentrators



May 16, 1967 E. REICHERT CONCENTRATE TAKE-OFF DEVICES FOR PINCHEDLAUNDER CONCENTRATORS Filed Aug. 26, 1964 3 Sheets-Sheet l l NYE NTO R:RNsT RE CHERT QA 51. 1; 51.04,

ATroR NE Y5 y 15, 1967 E. REICHERT 3,319,788

CONCENTRATE TAKE-OFF DEVICES FOR PINCHED LAUNDER CONCENTRATORS FiledAug. 26, 1964 3 heets-Sheet 2 INvEuroR:

ERNST RE 1c HE RT ATI'ORNEYS y 1967 E. REICHERT 3,319,788

CONCENTRATE TAKE-OFF DEVICES FOR PINCHED LAUNDER CONCENTRATORS FiledAug. 26, 1964 3 heets-Sheet 5 I I INVENTOR:

ERNSTREICHERT A rroRNE Ys United States Patent 3,319,788 CONCENTRATETAKE-OFF DEVIQES FOR PINCHED LAUNDER CQNCENTRATDRS Ernst Reichert,Southport, Queensland, Australia, assignor to Mineral Deposits Pty.Limited, Sydney, Australia, a company of Australia Filed Aug. 26, 1964,Ser. No. $2,246 Qlaims priority, application Australia, Sept. 3, 196334,934/63 Qlaims. (Cl. 209-493) This invention relates to the removal ofconcentrates from a stratified bed, of ore material to be treated, whichis moving as a stream along the bottom of a pinched launder. The streamconsists of a mixture of water, or other liquid, and particles ofdifferent specific gravities, such as ordinary sand and valuable heaviermineral particles. Examples of pinched launders to which the presentinvention is related, are those of the kind illustrated (and numbered33A and 45A) in the drawings forming part of the specification belongingto Australian Patent No. 247,676.

Concentrators of the pinched launder type are widely known in the fieldof gravity concentration of minerals. Usually the launders are ofchannel section narrowing towards the take-off end (which in use is thelower end) so to provide for gravitational feed of the ore material tothat end. Such launders have a flat floor with a transverse slot in itat the take-off end, through which the value fraction departs; thetailings leave the launder by falling from the lower end edge of thelaunder floor, and some kind of splitter blade or partition plate isprovided to ensure that the two falling fractions do not come togetheragain as they proceed to receiver vessels for further treatment, orfinal collection in the case of the values, and dumping in the case ofthe tailings.

In some instances, the launder floors are not slotted and in that casethe take-off end edge is confronted by a splitter which is directedupstream relative to the launder floor so to divide the Stratifiedstream leaving the launder into the required two fractions. As shown inthe mentioned prior patent, such a splitter may be height adjustable soto be variously positioned to accommodate streams of different valuerichness, or to enable the value fraction to be of greater or lesserpurity as may -be required.

It is also known, in slotted launders, to provide the door slot withadjustable shutter devices whereby the effective width of the slot maybe varied to suit variable factors of the kind referred to in theparagraph just above.

Prior launders of the kind discussed above are effective inconcentrating particulate ore materials of almost any degree ofrichness, and to almost any required degree of value purity, provided asufficient number of launders are used in cascaded series; butnevertheless, the prior launders are open to objection in severalrespects. For example; individual launders are not separativelycritical; that is, their use results in relatively large proportions oftailings staying with the values, or large proportions of values leavingwith the tailings, and hence large numbers of cascaded launders have tobe used if purity of output is required. Again, in the case of slottedlaunders, the abrasive nature of the ore quickly wears the slot-definingfloor edges so that the slots soon cease to be of the originallyselected required width. This requires replacement of the entire launderwhile the useful life of the major part of it is still substantiallyunimpaired. This also applies, to some extent, to slotted launderswhereof the slots are furnished with slot-adjusting shutters, in thatalthough total launder replacement may be necessary less frequently, itis difiicult, especially while 3,319,783 Patented May 16, 1967 theapparatus is in use, to make a shutter adjustment of definite andclearly observable magnitude.

The object of the present invention is to overcome or ameliorate one ormore of the mentioned shortcomings in a very simple way by the provisionof take-off devices for slotted launders of the kind indicated, which,in their simplest forms, provide a launder floor take-01f portion (thatpart of the floor in which the take-off slot or slots are provided)which is readily removable from the remainder of the launder and henceis simply and cheaply replaceable; moreover, such a provision enablesthe take-off floor portion to be made of a material less prone to wearby abrasion.

In the preferred embodiment of the invention a floorportion, as justmentioned, is provided; it has a plurality of particle departure slotstherein, and has combined threrewith simple splitter arrangements whichenable selected allocation of the slots, in terms of whether they arerequired to function as values slots or tailings slots, in a clearlyobservable manner irrespective of whether the launder is or is not inuse.

The invention consists primarily in take-off devices for concentratorpinched launders, comprising a take-off plate having at least onedeparture slot therein disposed laterally thereof, and means forremovably securing said plate in a gap in the floor of the launder withthe upper surface of the plate forming a continuation of, and a take-offportion for, said floor.

Examples of the invention are illustrated in the drawings herewith.

FIG. 1 is a perspective view showing the lower end portion of a pinchedlaunder with a plural-slot take-oft plate applied thereto.

FIG. 2 is a partly sectioned perspective view of the take-off plateshown in FIG. 1.

FIG. 3 is a sectional side elevation of the launder portion shown inFIG. 1 with an adjustable splitter asso ciated therewith.

FIG. 4 virtually repeats FIG. 3 except for its showing of an alternativeform of splitter.

FIG. 5 virtually repeats FIG. 3 except for its showing of the inventionapplied to a launder having a curved take-off portion.

FIG. 6 is a view similar to FIG. 3 showing modifications of bothtake-off plate and splitter.

Referring to FIGS. 1 and 2 the take-off plate 7 has four departure slots8 of selected predetermined width. This plate may be made in anysuitable way and of any suitable material. For preference it is mouldedout of rubber. Also for preference, the slots are defined by bars 9having sharply pointed lower edges 10 to act as shedding edges, so toensure against separated particles clinging to the under parts of theplate.

The floor 11 of the launder is gapped by reason of it ending at 12 whilethe launder side walls 13 extend beyond the end 12 to their own endfaces 14. The length of the take-off plate is preferably equal to thatof the floor gap as clearly shown in FIG. 1. In any event, the upstreamend 7A of plate 7 is required to abut against the launder floor end 12,so that the upper surface of the plate will remain in unbroken, andpreferably Lin-stepped, continuity with the launder floor; otherwise gapwould be present, between ends 7A and 12, which could operate as atake-off slot of indeterminate width. In this connection it will beappreciated that an important aspect of the invention resides in theability of the launder to give variable take-off proportions of valuesand tailings without any necessity for adjustability of take-off slotwidths; such adjustability being undesirable because of the difiicultyof making adjustments precisely or at all when the apparatus is in use.

There are many ways in which the take-off plate could be removablysecured in working position; for example, the side margins of the platecould be set-screwed or bolted to the underfaces of the side walls 13 orto fianges provided thereon. For preference, the side walls 13 areprovided with channel ways 15 in which side marginal portions of thetake-off plate are slideable with sufiicient tightness as will ensureagainst their dislodgment when in use. With such an arrangement it ispreferable for the platereceiving end portions of the side walls 13 tobe mutually convergent towards their free ends. This convergence need beno more than a few degrees of angle, being such that the wall endportions have to be sprung apart to enter the take-ofif plate betweenthem. This will ensure firm retention of the plate with its end 7A hardagainst the floor end 12. If desired the longitudinal sides of thetake-off plate may be similarly tapered, thus to hold the platewedge-locked in required working position.

it will be understood that any conventional kind of splitter could bepositioned with an edge uppermost below the take-off arrangement shownin FIG. 1 so to divide the output of the slots 8 into a value fractionpassing through a selected number of slots which are upstream, and atailings fraction which leaves the launder on the downstream side of thevalue slot or slots, by way of the open end of the launder (at the rightof FIG. 1) plus any of the slots not in use as value slots.

Instead of such conventional splitters however, those now to bedescribed are preferred.

Referring to FIG. 3, the splitter there shown consists of two side walls16, an oblique floor 17 having a dividing blade 18, and a roof 19 havinga locating lip 20. The two side walls 16 (only one is shown) are of thesame shape and size, and they are spaced apart sutriciently for thetake-off end of the launder to be easily entered between them. Thesplitter is supported by its roof resting on the tops of the side walls13 and is located by its lip 20 being entered in a selected one of aseries of notches 21 in each of the walls 13. In the splitter positionshown in FIG. 3 three upstream slots are in use as value slotscontributing to value stream 22; the remaining slot is in use to providea rich tailings stream 23 which may be diverted for retreatment, and atailings stream 24 which leaves the launder by way of its open lowerend. If desired, an extra splitter 25 may be provided to preventmingling of streams 23 and 24. If used, it may be held in positionsimply by jamming its upper offset end margin 26 between the underfaceof the plate 7 and the channel way portions just below that underface.

If stream 22 is found to be over-charged with non-value particles, thesplitter can simply be lifted and its lip relocated in a more upstreamslot 21.

The splitter shown in FIG. 4 is mounted on its launder in much the sameway as that described above in relation to FIG. 3. Its lip 27 is shownentered in a single notch 28. Clearly, a series of these notches couldbe employed for selective location of the splitter, but in thisembodiment there is less need to provide for relocation because of theadjustability of a divider blade 29. In this form of the invention thelower part of the splitter is formed as a pair of hoppers orcompartments 30 and 31. Hopper 30 has a values outlet 32, and hopper 31has a middlings outlet 33. Tailings leave as a stream indicated at 34.

Blade 29 is fixed on a shaft 35 in bearings in the side walls 36. Meansare provided for angularly adjusting the blade as indicated by dottedlines. These means (not shown) may consist of a handle fixed on one endof shaft 35 outside of the splitter and devices for holding the handlein selected adjustment. These devices could consist of a spring pressedball on the handle which rides a track having indentations in it tocorrespond with effective working positions of the blade 29.

The arrangement shown in FIG. 5 needs no description beyond saying thatit is the same arrangement as that shown in FIG. 3 as applied to thoselaunders in which the launder floor curves downwardly towards thedeparture end in order to enable the particles to accelerate as they areabout to leave the launder.

The form shown in FIG. 6 is a simple one for use where the compositionof the material under treatment remains substantially constant overrelatively long working periods. The splitter 37 can be fixedly mountedon the launder 38, the take-off plate 39 may have only two slots 40, andthe divider blade 41 may be fixed in its definition of values hopper 42and a middlings hopper 4 3. As before, tailings leave as indicated at44.

I claim:

1. In a concentrator launder having a floor and a gap in the floorpositioned generally at the outlet end thereof: a take-off devicecomprising in combination a takeoff plate having inlet and outlet endsand at least one departure slot therein disposed laterally thereofbetween its inlet and outlet ends, means for removably securing saidplate in the gap in the floor of the launder with the upper surface ofthe plate substantially forming a continuation of and take-off portionfor said floor, and a splitter including means for supporting thesplitter 0n the launder, said splitter further including a divider meanssituated below said take-off plate intermediate the inlet and outletends thereof and projecting upwardly towards the underside of saidtake-off plate.

2. The take-off device defined in claim 1 wherein said launder has apair of side walls extending generally on the opposite sides of saidtake-off plate, said side walls having a number of notches in the upperedges thereof, and wherein said means for supporting said splitter onsaid launder includes a top wall of the splitter and a lip projectingfrom the top wall and received in the notches in the side walls of thelaunder. I

3. The take-off device defined in claim 2 wherein said splitter furtherincludes a floor positioned below said takeoff plate, and a pair of sideWalls positioned outwardly of the side walls of the launder andinterconnecting said roof and floor of said splitter, said divider meansprojecting upwardly from the floor of said splitter.

4. The take-off device as defined in claim 3 wherein said divider meansprojects from one end of said fioor of the splitter and wherein saidfioor extends at an oblique angle with respect to the take-off plate.

5. The take-off device as defined in claim 3 wherein said divider meansprojects upwardly from said floor at a point intermediate the oppositeends of the floor and defines two hopper portions in said splitter, saidfloor having a pair of openings therethrough respectively formingoutlets communicating with said hopper portions.

6. The take-off device defined in claim 5 further includ ing means formovably supporting the divider means in selected positions spacedgenerally along the underside of the take-off plate.

7. The take-olf device defined in claim 6 wherein said divider means ismovable into opposite extreme posi" tions closing off either of saidhopper portions with respect to the slot in the take-off plate.

8. The take-off device defined in claim 7 wherein said means movablymounting said divider means includes a pivot means whereby said dividermeans is pivotally movable between its extreme positions, and whereinthere is further provided retaining means for holding the divider meansin selected angular positions.

9. The take-01f device defined in claim 1 further including a secondsplitter including a generally planar mounting portion received betweenportions of the launder located under said mounting plate and theunderside of said mounting plate, said second splitter further includinga divider portion extending from said mounting portion downwardly at theoutlet end of the take-off plate.

10. The take-off device as defined in claim 1 wherein said take-oilplate is made of molded rubber and has a plurality of departure slotstherein.

11. The take-ofif device defined in claim 10 wherein said take-oft ploteincludes integral bars having sharply pointed lower edges depending fromthe underside of said take-elf plate and defining said slots.

12. The take-off device defined in claim 1 wherein said launder hasopposite side walls and channel ways formed in the side walls generallybelow the level of the floor on opposite sides of said gap, said launderfloor having a transversely extending end portion also projectingdownwardly below the level of the floor at the inlet end of saidtake-off plate, said take-off plate being received in said channel wayswith the inlet end of said take-off plate in abutting engagement withsaid transversely extending end portion of said launder floor.

13. The take-off device defined in claim 12 wherein the launder sidewalls including the channel ways are mutually convergent towards theoutlet end and are resilient for retaining the take-off plate in thechannel ways.

14. A splitter device for use in conjunction with a concentrator pinchedlaunder of the type having a floor extending between inlet and outletends of the launder, a pair of side walls projecting upwardly from thefloor on opposite sides thereof, and a number of slots in the floorextending laterally of the floor; the splitter device ineluding a floor,opposite side walls projecting upwardly 25 from the floor, a roofportion adapted to be engaged on the upper edge of the launder sidewalls with the side walls of the splitter disposed laterally outwardlyof the launder side walls and with the splitter floor extending belowthe underside of the launder floor below the slots thereof, saidsplitter further including a divider means projecting upwardly from thesplitter floor and adapted to be positioned intermediate the inlet andoutlet ends of the launder, and means on the roof portion of saidsplitter for retaining the splitter in fixed position on the Walls ofthe launder.

15. The splitter device defined in claim 14 wherein said retaining meansincludes a downwardly projecting lip adapted to be engaged in acorresponding slot in the side walls of the launder.

References Cited by the Examiner UNITED STATES PATENTS 62,942 3/1867Curtis 209-397 2,875,898 3/1959 Spencer 209-493 X FOREIGN PATENTS1,358,078 5/1963 France.

969,759 7/1958 Germany.

HARRY B. THORNTON, Primary Examiner. L. H. EATHERTON, AssistantExaminer.

14. A SPLITTER DEVICE FOR USE IN CONJUNCTION WITH A CONCENTRATOR PINCHEDLAUNDER OF THE TYPE HAVING A FLOOR EXTENDING BETWEEN INLET AND OUTLETENDS OF THE LAUNDER, A PAIR OF SIDE WALLS PROJECTING UPWARDLY FROM THEFLOOR ON OPPOSITE SIDES THEREOF, AND A NUMBER OF SLOTS IN THE FLOOREXTENDING LATERALLY OF THE FLOOR; THE SPLITTER DEVICE INCLUDING A FLOOR,OPPOSITE SIDE WALLS PROJECTING UPWARDLY FROM THE FLOOR, A ROOF PORTIONADAPTED TO BE ENGAGED ON THE UPPER EDGE OF THE LAUNDER SIDE WALLS WITHTHE SIDE WALLS OF THE SPLITTER DISPOSED LATERALLY OUTWARDLY OF THELAUNDER SIDE WALLS AND WITH THE SPLITTER FLOOR EXTENDING